An escarpment (or scarp) is a type of cliff, formed by the movement of a geologic fault, or a landslide. Most cliffs have some form of scree slope at their base. In arid areas or under high cliffs, these are generally exposed jumbles of fallen rock. In areas of higher moisture, a soil slope may obscure the talus.
Primary Muscles. The primary muscles the plank works are the erector spinae, the rectus abdomimus and the transverse abdominus. The erector spinae is a large muscle that runs up the length of the back. It surrounds your spine and allows you to straighten your back and rotate side to side.he plank is one of the simplest and most effective abdominal exercises. In its most basic form, you brace yourself at the top of a pushup while contracting your core muscles. You can do multiple variations of the plank to create more challenge and target different parts of the core.
Secondarily, the plank targets shoulder muscles, the chest, and the front and back of the thighs. Variations on the basic plank, such as the side plank, target the oblique muscles -- the sides of the abs -- and the outer and inner thigh. Advanced exercisers can perform planks using the stability ball to improve balance.he plank is an exercise that works the bodyâs core, specifically the abdominal muscles and lower back. The exercise is traditionally performed as part of yoga and Pilates regimens but is effective for anyone looking to improve core strength and balance.